About The Cover

ONLINE COVER The Iron in the Fire of Hematopoiesis. This image shows molten iron, representing the focus of a study by Kao et al., where the authors linked the role of iron metabolism to unexpected benefits of a drug that bolsters platelets. Eltrombopag was designed as a thrombopoietin receptor agonist to stimulate platelet recovery for patients with thrombocytopenia, but clinical experience has shown that it also stimulates hematopoietic stem cell function in general, prompting a search for the underlying mechanism. The authors determined that in addition to its effects on the thrombopoietin receptor, eltrombopag chelates intracellular iron in hematopoietic stem cells, thus stimulating their activity. [CREDIT: THOMAS KOEHLER/PHOTOTHEK VIA GETTY IMAGES]